Onyvax-P
Onyvax’s Onyvax-P is a whole-cell allogeneic vaccine in Phase II development in the United Kingdom for CaP. The vaccine consists of three replication-deficient allogeneic cell lines representing cell types from different stages of the disease—primary tumor, secondary disease, and bone metastases. Onyvax plans to start a Phase III trial in the first half of 2005; manufacture of the vaccine for this trial is under way at Berna Biotech.
In an open-label Phase II trial involving 26 men with hormone-refractory CaP that had not metastasized to the bone, 11 patients were vaccinated monthly for one year. The profile of the patient group was favorable: median age was 67, median PSA at presentation was 11.1 ng / mL, and performance status was 0. Each month, patients received a mixture of the three cell lines (8 x 106 of each) supplemented with bacillus Calmette-Guerin (BCG) on weeks 0 and 2, followed by the three lines alone. All 11 patients experienced a prolonged reduction in PSA velocity. Median progression-free survival was 58 weeks. The most frequent side effects were fatigue and local injection-site reaction; no serious adverse effects occurred. Clinical delay in disease progression was correlated with evidence of immunological activation. Proliferation of patient T cells occurred after vaccination and cytokine responses were enhanced. Responding participants showed a mixed TH1- and TH2-type response rather than simply TH1 activation.